nazarijtipusak080/esp32-sd-card-read-write-append/sd-read-esp32

The node allows the ESP32 controller to read data from the SD card. IT IS IMPORTANT THAT THE FILE NAME MUST BEGIN WITH "/". OTHERWISE OPENING OR CREATING THE FILE WILL BE A NODE ERROR.

sd-read-esp32

@/sd-read-esp32

The node allows the ESP32 controller to read data from the SD card. IT IS IMPORTANT THAT THE FILE NAME MUST BEGIN WITH "/". OTHERWISE OPENING OR CREATING THE FILE WILL BE A NODE ERROR.

CSport

CS (chip select) pin the SD card reader is connected to. Also known as SS (slave select).

FILEstring

File name to append to

STARTnumber

CAPnumber

Rpulse

Perform file open, read, close cycle

POSnumber

STRstring

DONEpulse

Fires when write is done

To use the node in your project you should have the nazarijtipusak080/esp32-sd-card-read-write-append library installed. Use the “File → Add Library” menu item in XOD IDE if you don’t have it yet. See Using libraries for more info.

// This is the old sd-log patch migrated to the new v0.35 syntax method according to https://xod.io/docs/guide/migrating-to-v035/

#pragma XOD evaluate_on_pin disable
#pragma XOD evaluate_on_pin enable input_R
#pragma XOD error_raise enable



#include <SPI.h>
#include <SD.h>
size_t strlcpy(char *dst, const char *src, size_t size)
// Thanks to Adam Rosenfield for this funcion, strlcpy
{
    size_t len = 0;
    while(size > 1 && *src)
    {
        *dst++ = *src++;
        size--;
        len++;
    }
    if(size > 0)
        *dst = 0;
    return len + strlen(src);    
}


node {
    
    bool begun;
    char str[64] ;
 
    CStringView view = CStringView(str);
    
void evaluate(Context ctx) {
    if (!isInputDirty<input_R>(ctx))
        return;


    if (!begun) {
        // First time use, initialize
        auto csPin = getValue<input_CS>(ctx);
        SPI.begin(18, 19, 23, csPin); // SCK, MISO, MOSI, CS
        begun = SD.begin(csPin);
    }

    if (!begun) {
        // Initialization failed (wrong connection, no SD card)
        raiseError(ctx);
        return;
    }
    char filename[16] = { 0 };
    dump(getValue<input_FILE>(ctx), filename);
    File myFile = SD.open(filename, FILE_READ);
    if (!myFile) {
        // Failed to open the file. Maybe, SD card gone,
        // try to reinit next time
        begun = false;
        raiseError(ctx); // Can't open file
        return;
    }

    uint8_t START = getValue<input_START>(ctx);
    uint8_t CAP = getValue<input_CAP>(ctx);
    
    myFile.seek(START);

    uint8_t index = 0;
    //char ch[CAP+1];
   while (myFile.available() && index < CAP){
       char someChar = myFile.read();
      
       str[index] =someChar;
     
        index++;
       str[index] = '\0';
   }
  
    int pos = myFile.position();
    
    //strlcpy(str, ch, sizeof(str));
    
    myFile.close();
    
   emitValue<output_STR>(ctx, XString(&view));
   emitValue<output_DONE>(ctx, 1);
   emitValue<output_POS>(ctx, pos);


}
}

sd-read-esp32

nazarijtipusak080/esp32-sd-card-read-write-append/sd-read-esp32

C++ implementation